Polaris fuel sender info (carburetor engines)

I am putting together some data regarding Polaris PWC fuel senders. This is for the combination type with the fuel pickup and fuel level sender integrated into a single extruded aluminum unit inside the tank.

At the moment I am looking for some basic info, such as how far above the bottom of the fuel tank the aluminum tube style fuel sender sits.

First question; How much space/clearance is there between the bottom of the sender tube and the bottom of the actual fuel tank?

My understanding is that there are different sender part numbers for the different size/shape fuel tanks, and whether there is a 'Main' fuel nipple in addition to the Reserve fuel nipple.

How fuel depth relates to bars on MFD fuel level display

Working with a sample fuel level sender I happened to have on hand reveals the following data.

I made assumptions regarding how much of the fuel float actually floats above the fuel surface (7mm), how deep the tank goes below the sender bottom (10mm), and how tall the molded sender neck in the tank is.

It is interesting to note that when fuel is consumed down to first show 1 Bar there is still about 1/4 of the entire tank depth remaining (24% + 4%).

About 15% of the fuel depth from 'tank very full' must be burned off before the MFD display will drop to seven bars.

That leaves MFD bars 2 through 7 to cover the middle 'half' of the fuel tank.

The top 15% (roughly) of the tank is included in the eighth bar, and the bottom quarter of the tank is one bar and zero bars.

All this assumes the hull remains level and the fuel does not slosh around. To provide non-aerated fuel when actually riding the fuel pickup needs to be submerged deeper that the 'empty' number indicates.

Note that these numbers relate to fuel depth. Since the actual fuel tanks are not simple square shapes, the fuel capacity/volume per mm of fuel depth will vary.